Synonyms to unrepenting

callous, Philistine, anneal, apathetic, asleep, backed, benumbed, brazen, brutalize, calcified, calcify, calloused, case harden, case-hardened, cold, cold of heart, coldblooded, coldhearted, conscienceless, cornify, crusted, crusty, crystallized, dead, deadened, dull, firm, flinthearted, flinty, fossilize, fossilized, granulated, hard, hard of heart, hard-boiled, hard-nosed, harden, hardened, hardhearted, heartless, hornified, impassible, impenitent, imperceptive, impercipient, impervious, incrusted, indifferent, indurate, indurated, insensate, insensible, insensitive, insentient, insolent, inure, inured, lapidified, lapidify, lithify, lost to shame, numb, numbed, obdurate, obtuse, ossified, ossify, pachydermatous, petrified, petrify, proof against, reinforced, rigidified, sclerotic, seared, set, shameless, solidified, steel, steeled, steeled against, steely, stiffened, stony, stonyhearted, strengthened, temper, thick-skinned, thick-witted, tough, toughen, toughened, unabject, unblushing, uncaring, uncompassionate, uncontrite, unemotional, unfeeling, unfelt, unmelted, unmerciful, unnatural, unperceptive, unrepe